Abstract
The utilization of lanthanoid metal salts and organolanthanoid compounds as synthestic reagents or catalysts in organic synthesis has been steadily interesting due to their unique chemical properties. Low-valent, trivalent, and tetravalent lanthanoid compounds have been widely used in organic reactions, however, the direct use of lanthanoid metal is still rare due to their low solubility in organic solvents or their instability under aerobic conditions. In this paper, we show the various organic reactions by the direct use of lanthanum metal as a reagent. Various unstable carbon species, such as alkyl radicals, o-quinodimethane, carbene, benzyne and alkylidene carbene, were easily generated by the reaction of organohalogen compounds with lanthanum metal. Carbonyl compounds were also reduced by lanthanum metal and the generated reducing species were widely used on the new carbon-carbon bond formations. The synthesis of organochalcogenides was successfully achieved by the reaction of dichalcogenides, alkyl halides, and lanthanum metal.
